Means for maintaining a constant working level in glass-furnaces.



A; L. DAY.'

MEANS FOR MAINTAINING A CONSTANT WORKING LEVEL IN GLASS'FURNAGBS.

APPLIATIONPILED FEB. 6, 1912. d1 ,074,1 67, Patented sept. 3o, 1913.l

UNITED sTATEs PATENT oEEroE- .ARTHUR L. DAY, OF WASHINGTONLDISTRICT OF COLUMBIA, ASSIGNOB T EMPIRE MACHINE COMPANY, 0F PORTLAND, MAINE, A CCRPORATION 0F MAINE.

MEANS FOR MAINTAINING A CONSTANT WORKING LEVEL IN GLASS-FUB/NACES.

Specification of Letters Patent.

Patented sept. 3o, 1913.

Application led February 6, 1912. Serial No. 675,897. l

citizen of the United States of America, and

a resident of \Vashington, District of Columbia, have invented certain new and useful Improvements in Means for Maintaining Constant Vorking Levels in Glass- Furnaces, ofwhich the following is a sperification.

My invention has for its object to provide means whereby the level of the molten glass in the pool from which it is `taken for use in any of the various processes of its mamifaeture lmay be maintained constant. This constancy of level is of especial value in those processes in which the glass is gathered on the end of an iron which is dipped int-o the pool and withdrawn with a body of glass thereon, in that the amount of glass 'so gathered depends, among other things, upon the extent the iron is immersed, and because in the manufacture yof many articles the quantity of glass which is. so gathered upon the end of the iron must be uniform.

For the purposes stated my invention contemplates a gathering pool separate fromand independent of a main melt-ing pool,

and communicating therewith by a passage of restricted cross sectional area with means for varying the cross sectional area of the gathering pool at such a rate that the level of glass therein will be maintained constant in spite of the removal therefrom of the successive gathers. vThis variation in the cross section of the pool is accomplished autoliiatically by any departure of the glass level from normal. i y

The main melting pool has a relatively large. capacity as compared with that of the gathering pool and is replenished from time to time by fresh material as the consumption of glass from the gathering pool or pools connected therewith causes the level of the glass therein to lower. i

To prevent the varlations which would occur in the gathering pool under these conditions is the object of this invention, and

itl accomplishes this 'by reason of the fact that the area of the restricted passage is such that upon a variation of level in the gathering pool dueto the variation of the l,cross sectional area thereof it retards the ltransfer of molten glass from the pool of higher level to the pool of lower level.

For these purposes my mvention contemplates a furnace provided with a gathering pool and a melting pool and a communicating passage of restricted area between them, of a displacement block within the gathcring poel and means dependent upon a predetermined departure of the glassI in the latter from a normal level to vary the yelevation or depression of the block and thus etl'ect a corresponding variation in the capacity of the gathering pool,'\vhereby the glass in thelatter will be restored to its normal level and it further consists of the construction, arrangement and combination` o fl'O 1parts by whichV it is thus rendered poss1 e.

Referring to the accompanying drawings 1n whlch corresponding parts are designated by corresponding I narks of reference, Figure 1 1s a vertical fragmental section through a furnace having my invention applied thereto. Fig. 2 is a similar view taken at right angles to Fig. 1. Fig. 3 is a d'etail sectional view showing the mounting of the float and the contacts controlled thereby.

The furnace l is of usual construction, save that it has therein a transverse wall l'JL dividing its interior into a' melting pool or chamber 1b of comparatively great capacity and a gathering pool or chamber l, the two being in communication with each other throughthe restricted passage 1d formed in the Wall la. The gathering chamber is also shown as pr-ovided with boots 1e through which a gathering iron may be inserted.

A displacement block 2 is contained within the gathering chamber, and has a stem 2a projecting upwardly through the roof of thefurnace, the opening formed therein for this purpose being protected and closed by the water seal formed by a casing 2b mount-A ed on the furnace top and a bell 2 carried on the stem. The upper end of the stem terminates in a threaded extension 3, having thereon a nut 8a which rests upon the bearing i, of a bracket 4 suitably supported above the furnace. A worm upon the shaft 5, of an electric motor 5 mounted on the bracket, gears with the periphery of the nut so thatthe displacement block will be raised or lowered in the gathering chamber by the rotation of the motor, depending upon the -direction in which the latter is driven. Within the gathering chamber is also contained a float G of refractory material, having a stud (3a upon its upper face, which stud enters a suitable recess in the inner end of a lever 7, which extends through an openin 7a in the wall of the furnace and is pivote at 7b upon the exterior thereof and within a casing 7c surrounding and closing the said opening. An arm 7d extends upwardly from near the outer end of the lever and has its upper end connected by means of the adjustable link 7e with one arm of .a bell crank lever 7t pivoted at 7g within a dome 7h, upon the to of the casing 7U, the opposite arm of the' ever being located between two contact points 8 and 9, which are respectively connected to two wires 8L and 9a. A third wire 10a is connected to the dome 7". The wires 8a, 9a and 10EL form parts of two circuits, the wire 10a being a part of both, which circuits may either be led through the motor 5a to form energizing circuits therefor or be in the form of controlling circuits for the energizing circuit of the motor.

In order to protect the mounting of the levers, etc., from the excessive heat, I may as shown in Fig. 3, provide a pipe ll for introducing a current of air into the dome 7h, which flows through the dome and casing and into the furnace through opening 7 a.

The operation of the device is as follows: Upon the level of the glass in the pool being lowered, the float will lower 'and cause Contact to be made between the lever 7f and the contact 9, closing the circuit through the wires 9a and l0a and driving the motor to lower the displacement block, which, by reducing the cross sectional area of the gathering pool, raises the level of the glass therein. When this level has increased suficiently it will, by lifting the fioat, break the circuit between the wires 9a and 10, and arrest the motor. The difference of level thus created in the gathering pool over that in the melting pool is due to the fact that the passage ld has its area so restricted to retard the transfer of the molten glass from one pool to the other. IVhen, by further use of the glass from the gathering pool and the slow fiow of glass therefrom to the melting pool, the level of glass in the former is again reduced below the predetermined limit fixed by the adjustment of the level controller, the operation above described will be repeated and this will occur from time to time until the limit of lowering of the displacement block has been reached or until a fresh batch of glass is fed into the melting tank. As the level of glass rises in the latter, the molten glass will iow into the gathering pool and will raise the level of glass therein, closing the circuit between the wires 8l and 10a and causing the motor to llift the displacement block, thus increasino' the sectional area of the gathering pool and reduc-ing the glass level thereof, the action being the reverse of that before described, and will be repeated from time to time. It will also vbe seen that the apparatus here described provides means for retaining the level of the gathering pool constant, in spite of variations which would otherwise occur due to temporary excess of the rate at which the glass is gathered over the rate at which it Hows into the gathering pool. y

Having thus described my invention what I claim is l. In a glass furnace, the combination with a furnace having separate melting and gathering pools communicating with each other byV a restricted passage, of means actuated by a temporary variation of glass level in the gathering pool to vary the glass capacity of the gathering pool at a rate in l excess of the discharge capacity of the re-.vA

stricted passage, whereby the gathering pool will be restore level.

2. In a glass furnace, the combination with a furnace having separate melting and gathering pools communicating with each other by a restricted passage, of a displacement block, and means actuated by a temporary variation of level in the gathering pool to raise or lower the block in the glass therein, to effect a variation in the capacity of the gathering pool at a rate greater than the discharge capacity of the restricted passage whereby the glass in the gathering pool will be restored to normallevel. A

Intestimony whereof I have signed my name in presence of two witnesses.

l ARTHUR L; DAY. In presence of Y ALBERT L, KREY GEO. M. BOND.

to normal lass in the 

